Answer:
Option A is correct.
The wires will be arranged in order of increasing resistance.
Explanation:
The resistance of a wire is given by
r = (ρl)/A
where r = resistance of the wire
ρ = resistivity of the wire
L = length of the wire
A = cross sectional area of the wire
Provided all the other parameters are constant, resistance is inversely proportional to cross sectional area
r ∝ (1/A)
And the the cross sectional Area of the wire increases with increase in thickness & decreases with thickness
So, decreasing thickness ----> Decreasing Cross sectional Area ----> Increasing resistance.
When a body strictly moves on a curve, it's velocity at a point is tangential to the curve at that point.
Centripetal acceleration is the acceleration that a body experiences by the virtue of change in it's tangential velocity. It is directed towards the centre and mathematically is v^2/R where v is the speed at the instant.
So, 18 = v^2/R
v^2 = 504
v = 6√14
Answer : The change in enthalpy of the reaction is, -310 kJ
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given main reaction is,

The intermediate balanced chemical reaction will be,
(1)

(2)

(3)

Now we will reverse the reaction 1 and multiply reaction 1 by 2, reaction 2 by 2 and reaction 3 by 3 then adding all the equations, we get :
(1)

(2)

(3)

The expression for enthalpy of formation of
will be,



Therefore, the change in enthalpy of the reaction is, -310 kJ
Complete Question:
In the same configuration of the previous problem 3, four long straight wires are perpendicular to the page, and their cross sections form a square of edge length a = 13.5 cm. Each wire carries 7.50 A, and the currents are out of the page in wires 1 and 4 and into the page in wires 2 and 3.
a) Draw a diagram in a (x,y) plane of the four wires with wire 4 perpendicular to the origin. Indicate the current's directions.
b) Draw a diagram of all magnetic fields produced at the position of wire 3 by the other three currents.
c) Draw a diagram of all magnetic forces produced at the position of wire 3 by the other three currents.
d) What are magnitude and direction of the net magnetic force per meter of wire length on wire 3?
Answer:
force, 1.318 ₓ 10⁻⁴
direction, 18.435°
Explanation:
The attached file gives a breakdown step by step solution to the questions